ABSTRACT
Spinocerebellar ataxia type 10 (SCA10) is a rare autosomal dominant ataxia caused by a large expansion of the (ATTCT)n repeat in ATXN10. SCA10 was described in Native American and Asian individuals which prompted a search for an expanded haplotype to confirm a common ancestral origin for the expansion event. All patients with SCA10 expansions in our cohort share a single haplotype defined at the 5'-end by the minor allele of rs41524547, located ~35 kb upstream of the SCA10 expansion. Intriguingly, rs41524547 is located within the miRNA gene, MIR4762, within its DROSHA cleavage site and just outside the seed sequence for mir4792-5p. The world-wide frequency of rs41524547-G is less than 5% and found almost exclusively in the Americas and East Asia-a geographic distribution that mirrors reported SCA10 cases. We identified rs41524547-G(+) DNA from the 1000 Genomes/International Genome Sample Resource and our own general population samples and identified SCA10 repeat expansions in up to 25% of these samples. The reduced penetrance of these SCA10 expansions may be explained by a young (pre-onset) age at sample collection, a small repeat size, purity of repeat units, or the disruption of miR4762-5p function. We conclude that rs41524547-G is the most robust at-risk SNP allele for SCA10, is useful for screening of SCA10 expansions in population genetics studies and provides the most compelling evidence to date for a single, prehistoric origin of SCA10 expansions sometime prior to or during the migration of individuals across the Bering Land Bridge into the Americas.
ABSTRACT
AIMS: The objective of this study was to examine associations between elevated depressive symptoms and increased risk of adverse clinical events patients with heart failure and reduced ejection fraction (HFrEF), as well as the potential contribution of health behaviours. METHODS AND RESULTS: One hundred forty-two men and women with HFrEF were enrolled through heart failure (HF) clinics and followed over time. At baseline and 6 months, depressive symptoms were assessed by the Beck Depression Inventory-II (BDI-II) and HFrEF disease activity by B-type natriuretic peptide (BNP). The Self-Care of Heart Failure Index (SCHFI) was used to assess HF self-care behaviours. Proportional hazards regression models assessed the contribution of depressive symptoms and HFrEF disease biomarkers on death or cardiovascular hospitalization. Over a median follow-up period of 4 years, 42 patients (30%) died, and 84 (60%) had cardiovascular hospitalizations. A 10-point higher baseline BDI-II score was associated with a 35% greater risk of death or cardiovascular hospitalization. Higher baseline BDI-II scores were associated with poorer HF self-care maintenance behaviours (R = -0.30, P < 0.001) and fewer daily steps (R = -0.19, P = 0.04), suggesting that elevated depressive symptoms may diminish important health behaviours. Increases in plasma BNP over 6 months were associated with worse outcomes. Changes in BDI-II and plasma BNP over 6 months were positively related (R = 0.25, P = 0.004). CONCLUSIONS: This study confirms that elevated depressive symptoms are associated with an increased likelihood of adverse clinical outcomes in patients with HFrEF. Poor health behaviours may contribute to the adverse association of elevated depressive symptoms with the increased hazard of adverse clinical outcomes.
ABSTRACT
Insomnia and poor sleep are associated with an increased risk of developing cardiovascular disease (CVD) and its precursors, including hypertension. In 2022, the American Heart Association (AHA) added inadequate sleep to its list of health behaviors that increase the risk for CVD. It remains unknown, however, whether the successful treatment of insomnia and inadequate sleep can reduce heightened CVD risk. SLEEPRIGHT is a single-site, prospective clinical trial designed to evaluate whether the successful treatment of insomnia results in improved markers of CVD risk in patients with untreated hypertension and comorbid insomnia disorder. Participants (N = 150) will undergo baseline assessments, followed by a 6-week run-in period after which they will receive cognitive behavior therapy for insomnia (CBT-I), comprised of 6 hourly sessions with an experienced CBT-I therapist over a 6-week period. In addition to measures of insomnia severity, as well as both subjective and objective measures of sleep, the primary outcome measures are nighttime blood pressure (BP) and BP dipping assessed by 24-h ambulatory BP monitoring (ABPM). Secondary outcomes include several CVD risk biomarkers, including clinic BP, lipid profile, vascular endothelial function, arterial stiffness, and sympathetic nervous system (SNS) activity. Data analysis will evaluate the association between improvements in insomnia and sleep with primary and secondary CVD risk biomarker outcomes. The SLEEPRIGHT trial (ClinicalTrials.Gov NCT04009447) will utilize CBT-I, the current gold standard treatment for insomnia disorder, to evaluate whether reducing insomnia severity and improving sleep are accompanied by improved biomarkers of CVD risk in patients with untreated hypertension.